Light projector



Jan. 3, 1933. R. w. LEwls v 1,892,898

lLIGHT PROJECTOR Filed April 2l, 1921 2 Sheets-Sheet 2 Patented Jan. 3, 1933 RICHARD W. LEWIS, OF NEW YORK, N'. Y.

Lienr rnoino'roa Application led April 2l, 1921. Serial No. 463,350

(GRANTED UNDER THE ACT 0F MAECI-1.3, 1883, AS AMENDED APRIL 3G, k1928.; 370 0. G. 757) This invention described herein may be manufactured and used by or for the Government for governmental purposes, Without the payment to me of any royaltyV thereon.

This invention generically relates to searchlight construction; more specifically it is directed to a new and improved light projector of the high intensity drumless type particularly applicable to military and naval operation.

The fundamental purpose of this invention is to produce a simple, inexpensive light projector, affording a more effective utilization of the light rays, While dispensing with many of the-complicated, cumbersome features of the prevailing designs.

Another important object of this invention is to design a light projector which eliminates the usual enclosing barrel and its incidental structure and substitutes in lieu thereof a shielded arc source located'in advance of the reflector. 4

With these and other objects in view, this invention consists of certain novel details in construction, combination and arrangement of parts to be more fully hereinafter set forth and claimed. Y

Briefly stated, this invention embodies a large drumless reflector, operable horizontally and vertically to any desired angle, and a shielded arc source situated in front of and in suitable optical relation with respect to the reflector to produce a reflected beam.

Referring more particularly to the accompanying drawings, in which `corresponding parts are indicated by similarv reference characters:

Fig. l is a perspective view of the projector forming the subject matter of this application.

Fig. 2 is a similar View, the reflector in its mounting being revolved to illustrate the arc mechanism and controlling means.

Fig. 3 is a transverse vertical section through the reflector, its mounting andthe arc shield, the arc mechanism being shown in elevation.

Fig. 4 is an enlarged transverse section through the arc source shielding means.

According to prevailing designs, light f projectors of the high intensity type embody a cylindrical casing or barrel provided at one end with a reflector and equipped at the other With a glass closure, the arc source being located Within the casing intermediate the reflector and closure.

These projectors are not only expensive to produce but are extremely heavy and cumbersome rendering transportation diicult and greatly restricting the field of searchlight usefulness. Moreover, experience With the present type of searchlight has Vdemonstrated that a certain amount of stray light is reflected from the sides of the barrel, and that portions of the arc flame Which are outside the crater produce a considerable amount of foreground illumination and dispersed lightv which is undesirable in military and naval operations, as it illuminates the immediate vicinity of the searchlight and interferes With the observation of the objective.

It is therefore the aim and purpose of this invention to produce a searchlight which will have a materially extended field of usefulness, eliminate the problems of stray light,

foreground illumination, ventilation and j, and enable a projector of the` high inten type to be constructed Which is simple in design, devoid of complicated arc mechanism, and of a Weight to enable conc venient transporting of the projector to meet varying field conditions.

ln the illustrated embodiment characterizing this invention, reference being had especially to Figs. l and 2, there is shown a carriage comprising a rectangular frame l, front and rear axles 2, Wheels 3, a turn table l, mounted upon the frame and operating upon rollers 5, and oppositely disposed trunnion supporting arms 6 extending upwardly CTI CII

from the turn table. This structure forms no part of the present invention and is referred to for descriptive purposes only.

ln order to facilitate further discussion of this invention, it Will be hereinafter considered under the following headings: reflector mounting, arc mechanism, and arc shielding lnftlllS.

Heyt'ector mounting To enable the reflector to be positioned at any desired angle, a mirror frame 7 is pivotally mounted between trunnion supporting arms G on trunnion supporting shafts Frame 7 is formed With radial ribs 10 supporting an annular rim 11 Within Which is positioned a parabolic mirror 12 having a cen ral opening 13 adapted to receive centering hub 9.

Arc mechanism The simplified arc mechanism which it is proposed to use With this invention, embodies a positive carbon 14, mounted in a carbon holder 15, secured to one end of a control rod 1G. This rod 16 extends to the rear of the casing through a tubing 17 Within Which it is slidably house l. The negative carbon 1S is co-axia-lly supported with respect to the positive carbon 1st by a holder 19 secured to one end of a control rod 2O which also extends to the rear of the reflector. The free ends of rods 16 and 20 are provided With operating knobs 21 and 22. Manifestly, by this arrangement the operator may readily strike the arc and otherwise adjust the carbons from a peint to the rear of the refiector.

Arc shielding means The arc mechanism is partially enveloped by a tubular shield or casing 23 open at its inner end and horizontally mounted upon the free end of a tube 1'? extending from hub 9 of the frame. lVith the shield positioned in this manner all rays other than those directed to the reflector are absorbed so that foreground illumina-tion and other objectionable features are avoided.

ln conclusion, it is evident that a projector constructed in accordance with the principles previously outlined, possesses the various essentials necessary to field usage, to Wit portability, simplicity, accessibility of the arc mechanism, reliability, self ventilation, and manual control, the operation of the light being independent of the automatic feeding or other a xiliary devices usually employed for controlling the arc and ventilatinfr the barrel.

Although in the foregoing certain elements have been defined as best adapted to performing the functions allotted to them, nevertheless it is to be understood that various minor changes as to the particular type of arc mechanism used, character of reflector, etc., may be resorted to Without departing from or sacrificing any of the principles of this invention.

Having now defined my invention, what l claim as new and Wish to secure by Letters Patent is:

1. A light projector comprising in combination, a frame, means for adjusting said frame in azimuth and elevation said frame having a central tubular extension, a reflector seated in the frame, a shield supported on the free end of said extension and an arc mechanism partially inclosed by the shield and including control rods extending to the rear of the reflector, one of the rods passing through the tubular member.

2. A light projector comprising 'a combination, a frame, means for adjusting said frame in azimuth and elevation said frame having a central hub, a reflector seated in the frame and centered by the hub, a tubular member extending from the hub, a shield supported on the free end of said member, and an arc mechanism partially inclosed by the shield and including control rods extending to the rear of the refiect-or, one of the rods passing through the tubular member.

3. A light projector comprising in combination, a frame, means for adjusting said frame in azimuth and elevation said fram having a central tubular extension, a rcfiect-or seated in the frame, a shield supported on the free end of said tubular extension, an arc mechanism partially embraced by the shield and including control rods extending to the rear of the reflector, one of the rods passing through the tubular member, and means in connection with the outer end of the shield excluding the entrance of air currents While permitting escape of the products of combustion.

4. A light projector comprising in combination, a frame, means for adjusting said frame in azimuth and elevation said frame having a central tubular extension, a reflector seated in the frame, a cylindrical shield open at its inner end and supported on the free extremity of said tubular member in such a manner that its long axis Will be parallel to the long axis of the said tubular extension, an arc mechanism partially embraced by the shield and including control rods extending to the rear of the reflector, one of the rods passing through the tubular member, and means in connection with the outer end of the shield excluding the entrance of air currents While permitting escape of the products of combustion.

5. A light projector comprising in combination, a frame, means for adjusting said frame in azimuth and elevation said frame having a central hub, a reflector seated in the frame and centered by the hub, a cylindrical shield open at its inner end and supported on the free end of said member having its long axis parallel to the central axis of -the hub, an arc mechanism partially em-y braced .by the shield and including. control rods extendingto the rear of the reflector .and with one of the rods passing through said tubular-member, and means in connection" With the outer end of the shield eX- cluding the entrance of air currents While electrodes, electrode'controls extending from a point tothe rear of the mounting'through itscentral portion to points in advance of the reflector, means in connection with the projected extremities of the controls tosup port the-electrodes with their axes coincident with the optical aXis of the reflector, a shield open at its inner end and partially embracing the arc mechanism enclosing the arc source and absorbing unreflected light rays, and means in connection with the outerend of the shield excluding'the'entrance of air'currents While permitting escape of the products of combustion.

7. AnV open type searchlig-ht comprising in combination a reflector formed with an annular opening, a mounting for the reflector a hub member located Within the opening, an arc mechanism supported by the mounting and including a pair of coaxially arranged electrodes, electrode controls extending from the rear of the mountingthrougL the hub member to points in advance of said reflector, means in connection-With the projected eX- tremities of the controls to support vthe latter With their axes coincident with that of the optical axis of the reflector, a shield open at its inner end and partially embracing the arc mechanism enclosing the arc source and absorbing unreflected light rays, and means in connection with the outer end of the shield excluding the entrance of air currents While permitting the escape of the products of combustion. Y

8. An open type searchlightcomprising an are lamp including the regulating mechanism th-erefor, a reflector having a centralv opening, a mounting for the reflector, and means on the mounting concentric with said opening for supporting the arc lamp. with its regulating mechanism in position With the arc at the 'focus of the reflector.

9. An open type searchlight comprising an arc lamp including the regulating mechanism therefor having manual controlling means at one end thereof, a reflector having a central opening, a mounting for the reflector, and means on the mounting arranged concentric with said opening for-supporting the arclamp with the manualcontrolling means in the rear of the reflector.

10. An open type searclilight comprising an arc lamp-including the regulating mechanism therefor, a reflector having a central opening, a mounting for the reflector, means on the mounting concentric with said opening for supporting the arc lamp with its regulating mechanism and manually actua-ted means for locating the light emitting element of the lamp in the focal region of the reflector from the rear of the reflector.

11. In a flaming arc open type searchlight, the combination With the electrodes, of a relector, means for supporting the positive and negative electrodes in the open air so that the positive points toward said reflector and the negative lies between the positive and the reflector, and a hood enclosing the space ad apted to be occupied by the arc and adapted to cut off the light therefrom on all sides eX- cept therside nearest to said reflector, said hood extending toward said reflector to such distance as to cut off all rays of light from the arc beyond the limits of said reflector.

'12. An open type searchlight comprising a reflector, a supporting shallow shell, a pivotal mo-unting for said shell and reflector, arc lamp mechanism for supporting the electrodes in front of said reflector,- and at least partially lWithout said shell, including a shield for inclosing the arc on three sides, and means for supporting said mechanism from the shell.

13. An open type searchlight comprising in combination With the reector, a supporting shell or back therefor, a pivotal mounting for said back, arc lamp mechanism for supporting the electrodes above the reflector and back, a shield for the arcing tips of the electrodes and means for supporting said mechanism and shield from said baclr.

14. A n open type searchlight comprising in combination With the reflector, a supporting shell therefor, a pivotal mounting for the shell, arc lamp mechanism for supporting the electrodes above the. reflector', a shield for the arcing tips of the electrodes, an exhaust flue-connected therewith, and means for supporting said mechanism and shield from said shell.

15. An open. type .flaming arc searchlight comprising the combination with the reflector and a supporting backing therefor, electrode holders for the electrodes, adapted to support the positive electrode facing the reflector-and the negative between said positive and the reflector, means for supporting said holders above-all parts of said reflector and backing and a hood enclosing the arcing tip of the positive electrode and adapted to cut olf the light therefrom on all sides exceptV the side facing the reflector for the purpose specified.

16. An open type searchlight comprising an arc lamp including the regulating mechanism therefor, a reflector, a mounting for the reflector and means on the mounting Vfor sup'- lli) ico

porting the arc lamp with its regulating mechanism in position with the arc at the focus of the reflector.

17. An open type searchlight comprising an arc lamp including` a regulating` mechanism therefor, having manual contrat ling means at one end thereof, a reflector, a mounting for the reflector and means on the mounting arranged concentric with said opening for supporting the arc lamp With its manual controlling means in the rear of the reflector.

18. An open type searchlight comprising an arc lamp including a regulating mechanism therefor, a reflector, a mounting for the reflector, means on the mounting for supporting the arc lamp With its regulating mechanism, manually actuated means accessible from the rear of the reflector for locating the light emitting element of the lamp in the focal region of said reflector.

19. An open type searchlight comprising an arc lamp including the regulatingr mechanism therefor, a reflector, a mounting for the reflector, means in connection With the mounting for supporting the arc lamp With its regulating mechanism in position With the arc at the focus of the reflector, and a shield partially enclosing the arc and adapted to cut off all light rays except those striking the reflector.

20. An open type searchlight comprising an arc lamp including the regulating mechanism therefor, having manual control means at one end thereof, a reflector, a mounting for the reflector, means on the mounting for supporting the arc lamp with the manual controlling means in the rear of the reflector, and a shield partially enclosing the arc and adapted to cut oil all light rays except those striking the reflector.

2l. An open type searchlight comprising an arc lamp including the regulating mechanism therefor, a reflector, a mounting for the reflector, means in connection with the mounting for supporting the are lamp with its regulating mechanism, a shield partially enclosing the arc and adapted to cut off all light rays except those striking the reflector, and manually actuated means accessible from the rear of the reflector for locating the light emitting element of the lamp in the focal region of the reflector.

22. An open type searchlight comprising au arc lamp including the regulating mechanism therefor, a reflector and mounting for the reflector, means in connection With the mounting for supporting the arc lamp with its regulating mechanism in posit-ion with the arc at the focus of the reflector, a shield partially enclosing the arc and adapted to cut off all light rays except those striking the reflector, and exhaust means connecting the exterior with the interior of said shield to remove the exhaust fumes.

23. An open type searchlight comprising an arc lamp including the regulating mechanism therefor, having manually controlled means at one end thereof, a reflector, a mounting` for the reflector, nieans in connection with i l l the mounting for supporting the are lamp With the manual control means in the rear of the reflector, a shield partially enclosing the arc and adapted to cut off all light rays except those striking the reflector, and exhaust moans connecting the interior With the exterior of said shield to remove the exhaust fumes.

24. An open type searchlight comprising an arc lamp including the regulating mechanism therefor, a reflector having a central opening, a mounting for the reflector, said mounting being formed with an annular boss adapted to project through the opening in the reflector, means in connection with said extension for supporting the arc lamp With its regulating mechanism in position With the arc at the focus of the reflector, and a shield partially enclosing the arc and adapted to cut off all light rays except those striking the reflector.

25. An open type searchlight comprising an arc lamp including the regulating mechanism therefor, having manual controlling means at one end thereof, a reflector having a central opening, a mounting for the reflector, a boss on the mounting arranged concentric Wifh and adapted to project through said opening, said boss supporting the arc lamp with the manual controlling means in the rear of the mounting, and a shield partially enclosing the arc and adapted to cut off all light rays except those striking the reflector.

2G. An open type searchlight comprising an arc lamp including the regulating mechanism therefor, having manual controlling means at one end thereof, a reflector having a central opening, a mounting for the reflector, a boss on the mounting arranged concentric With and adapt-ed to project through said opening, in the reflector, said boss supporting the arc lamp with the manual controlling means in the rear of the mounting, a shield partially enclosing the arc and adapted to cut ofi1 all light rays except those striking the reflector, and means connecting the interior with the exterior of said shield to remove exhaust fumes.

27. An open type searchlight comprising an arc lamp including a regulating mechanism therefor, a parabolic reflector, al swivelled mounting for the reflector to permit its adjustment in azimut-h and elevation, means in connection With the mounting for supporting the arc' lamp with its regulating mechanism in position With the arc at the focus of the reflector, and a shield partially enclosing the arc and adapted to cut ofl' all light rays except those striking the reflector.

28. An open type searchlight comprising an arc lamp including a regulating mechanism therefor, a parabolic reflector, a swiw elled mounting for the relector adjustable in azimuth and elevation, means in connection with the mounting for supporting the arc lamp With its regulating mechanism in position with the arc at the focus of the re- Hector, a shield partially enclosing the arc and adapted to cut off all light rays except those striking the reflector, and exhaust means connecting the interior With the exterior of said shield to remove the exhaust fumes- RICHARD W. LEWIS.. 

